Add Windows code

Tests/X11/CMakeLists.txt

@@ -5,7 +5,11 @@ INCLUDE (${CMAKE_ROOT}/Modules/FindX11.cmake)
 
 IF(CMAKE_HAS_X)
   INCLUDE_DIRECTORIES(${CMAKE_X_CFLAGS})
+  ADD_DEFINITIONS(-DCMAKE_HAS_X)
+ENDIF(CMAKE_HAS_X)
 
-  ADD_EXECUTABLE (X11 X11.c)
+ADD_EXECUTABLE (X11 X11.c)
+
+IF(CMAKE_HAS_X)
   TARGET_LINK_LIBRARIES(X11 ${CMAKE_X_LIBS})
 ENDIF(CMAKE_HAS_X)

Tests/X11/X11.c

@@ -1,3 +1,5 @@
+#ifdef CMAKE_HAS_X
+
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 
@@ -36,3 +38,11 @@ char **argv;
 }
 
 
+#else
+
+int main()
+{
+  return 0;
+}
+
+#endif